user
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.

### Instruction:
Identify which of the following is a primary source and which is a secondary source.

### Input:
A book written by a historian about World War II and a diary written by a soldier during World War II

### Response:
assistant
The diary is a primary source and the book is a secondary source.